DESCRIPTION (Taken from application) This analytical core will be housed at Lamont-Doherty Earth Observatory (LDEO) and will provide sample preparation and analyses to multiple projects of this Superfund application. This core will primarily support Project 8 (Persistent organochlorines in the Hudson River Watershed) and Project 2 (Sources and pathways of heavy metal exposure in the Hudson River Watershed and New York City). In addition, exploratory Pb isotope analyses will be made on pre-ashed blood samples from Project 3 in year 3. If these exploratory analyses prove useful, then supplemental funding will be sought at that time to expand the number of Pb isotope analyses being run for Project 3. Sample preparation will include the following matrixes: soil, sediment and particulate matter filters, as well as sample preparation on a limited number of pre-ashed blood samples. Work to be performed for Projects 8 and 2 include sample preparation and radionuclide measurements via gamma spectroscopy and stable Pb isotope measurements. Additional analyses to be performed for Project 2 include Hg concentration and multi-element analyses by flame AA and ICP-MS. Work to be performed for Project 3 in Year 3 includes sample preparation and Pb isotope analysis of pre-ashed blood samples.